Timer



June 10, 1952 w, NOQN 2,599,858

TIMER Filed Sept. 26, 1950 Invert/for Alonzo WNoon Patented June 10, 1952 UNITED STATES PATENT OFFICE TIMER Alonzo W. Noon, San Diego, Calif, assignor of one-third to'Asa H. Rix and one-third to Roy A.- Noon, both of San Diego, Calif.

-Appli'cation Septeiriher 26, 1950, Serial'No: 186,718

7 Claims. (01.- 161 -1) Thelipresentinvention relates to timers ingeneral and particularly to 'a timer of great'accuracy capable of opening and'closing electrical circuits. More specifically the invention comprises a timer adapted- 'tocontrol an electrical circuit following a predetermined time delay subsequent to the occurrenceofan event an'd'which is instantly reset.

The control of machines, apparatuses, and circuitsfrequently requires that they be actuated following" the occ'urre'nce of "some determinative action or-ev'ent. It is frequentlynecessary to provide 3a time delay between the determinative 'eventand the actuation of the-apparatus, device, or circuit, and where the "event is repetitive the time delayshould be'consta-nt" and accurate to a high degree. Timers i-nwhich the time delay is e'ffec'ted by TOICingTafixed volume of air under' a predetermined load through a' discharge port or oriflceare common. Such devices-are of great usefulness but there-is particular needfor timers of gr'eater accuracy 1 and which are free from variations due' to .cha-nges in' atnio'spheric conditionsfwearj and "other variables. It is also important in 'many'oontrQIs which are repetitive that-'the'd'evice be' 'resetat: great speed in order that it ina'y -be' readyior immediate reoperation. This requires-a timeroperating with a time delay inone direction' but which is instantly reset.

With'air appreciation -'of the problems characterizing the field 'of controls it is an object of the :pr'esent'invention to providea new'an'd improved timer i-n' which a predeterminedresultant act is fi'ected 'at -a--predetermined time interval following the occurrence ofa'preselectedprior event 7 and'in which the time delay'interval is free from variatibnsdue to exterior-conditions.

'It is' a'nother-Iobject of the 'invention to provide 1a control timer in which the delay period'is extremely accurate and in which the'resetting operation-is substantially instantaneous.

lit is still -another object of'fltheinvention to provide a" new and improved timer control mechahism in'wh-ich'the timerimpresses a predeterinin'd time delay 'betwe'en the occurrence of certain operauons and-in whiizh the unit is re oriented 'for' a 'subsequ'ent use"in a time interval "which is'j-f-ra'ctional "as-related to the delay period =menti'o' d.

These ailagemer' more specific-objects will appear upon reading; thefollowin'gspecification and "claims" 'andiiponconsiderate-in connection therewith the attached drawing to which they relate. I Referring-now to-the drawinginwhich a'pre- "'ferred' embodiment of 'theini e'r it'ion" is illustrated:

Figure" 1- isatop sian Vi'W of the timer con i 2 structed in accordance with-the presentinvention; I

Figure 2 is an endelevational view looking in the direction'of thearrowsupon the line 2--2fof Figure 1; and V Figure 3 is a-section-upcn the plane of the'line 83 of Figurel. a

The timer constructed in accordance withthe present invention is a relatively simple but highly accurate device. It may bedividedbroadly into five main parts comprising -a driving motor iii; a unidirectional flywheel unit, indicated-generally by the reference character H; a torque spring lily-a control switch, indicatedgenerally by the reference character 13; and a frame,fin dicated generally by the reference character l4. Driving motorlfi-compr-ises a torque motor. which receives current from a circuit comprising leads 6- and l the-flow of current in whichis controlled by aswitchtthe actuation of which is related to the-event-oroccurrence initiating the period known -as'the timedelay period. The motorv includes-a-casing I6 fixedly mounted at one end of thebase ll of frame M. Its'shaft I9 rotates with theunshown armature and extends abovelthe frame base ll being connected by a collar 2| to 'an'aligned shaft 22 rotatably -mounted in an-end wall or plate 23 forming a part of frame unit l 4.

A large diameter gear- 25 is fixed to shaft 22 adjacent collar 2 I by its own securing,- eollar- 21 androtates with the shaft whicheofacourse, by virtue of the connection of collar 2 l, rotates with the motor shaft 19.

fixedly in the frame'wall 23 whileitsoppesite end 29 seats fixedly in the gear 28 as by extending into an aperture therein. Spring l2 isa ca-refully calibrated spring theitorque of whichisrelated'with-accuracy to the mass-it-isadapted-to rotate and to'the inertia it must overcome-in the operation of the device, as will be further-described. Spring I2 is so connected between the fixed frame'wal1'23 and thegear26 that it'tis The torque spring l2-encircles shaft 22 :withone of its ends 28 seated pivoted, slidable, or mounted for any suitable motion so long as its displacement actuates the internal contacts of switch proper 3|. The latter may be a conventional switch but preferably is of the micro-switch type. The leads 33 and 34 which connect to it are a part of the electrical circuit to be controlled by the timer unit. The switch may be so connected into the circuit as either to close or to open it when actuated.

The operation of switch 3| is accomplished by the displacement of plunger 32 by a lever arm 38 carried fixedly upon the extended end of shaft 22 and so positioned as to make contact with plunger 32 when moving between its end positions as determined by stop pins 38 and 35 which extend outwardly from frame wall 23. Lever 38 has its own securing collar 4| by which it is clamped to shaft 22 and its outer end at its leading edge is chamfered and inclined as to provide a cam surface at 42 where it makes initial contact with switch control plunger 32. With motor I6 energized lever 36 is held against stop 38 but upon the de-energization of the motor the lever rotates with its carrying shaft 22 in a clockwise direction, as viewed in Figure 2, that is, from its position adjacent stop pin 38 toward and into contact with stop pin 39. Before reaching the latter lever 36 makes contact with and actuates switch plunger 32.

To provide the time delay period desired between the occurrence of the event which effects the de-energization of the motor and the actuation of the switch 3|, reliance is placed upon the flywheel unit The latter is seen to comprise a relatively large diameter flywheel 44 mounted for free rotation upon a shaft 46 and having a mass which is great as compared to the parts to which it is related. The opposite end of shaft 48 has clamped to it by a collar 45 a toothed pinion 41 in mesh with the large diameter motorand spring-driven gear 28. The shaft extends parallel to shaft 22 and is mounted for rotation with a minimum of friction by means of bearings 48 countersunk at the outer ends of the bore 49 through which the shaft extends in the end wall 23.

It is desired that the shaft 48 be free to rotate without movement of flywheel 44 during the resetting operation in which the gear 26 is turned by motor ID to load the spring l2 and in which the actuating lever 38 is being repositioned adjacent stop pin 38. To accomplish this result a unidirectional clutch is provided comprising a circular plate or disc 53 secured by means of its clamping collar 54 to the end of shaft 46 adjacent flywheel 44. Upon diametrically opposite sides of the disc 53 are positioned a pair of smaller discs, indicated generally by the reference character 56, which are eccentrically mounted by means of pins 51 upon the side of flywheel 44 in such positions that their peripheral surfaces contact the peripheral surface of disc 53. Spring elements 58 fixed upon pins 59 also secured to the side of flywheel 44 at all times exert a pressure against the central larger disc 53, the springs being so positioned with respect to the pins 51, which support the discs 56 eccentrically, that the spring force tends to wedge the discs 56 between the pins and the disc 53. The relationship is one characteristic of unidirectional clutches or drives in that upon the rotation of shaft 46 and with it the central driving disc 53 in one direction, clockwise as viewed in Figure 2, the peripheral surface of disc 53 exerts a force upon the discs 58 opposing the forces exerted by their springs 58 and tends to move them from Wedging relationship. This clockwise direction of rotation referred to is the direction in which the disc 53 is driven by the motor l8. Upon the rotation of the shaft 46 and disc 53 in the opposite direction, however, that is, counterclockwise as viewed in Figure 2, the frictional force exerted by the central disc 53 upon the contacting smaller discs 56 supplements the forces exerted by the spring elements 58 and the smaller discs are wedged between the central disc and their pivotal pins 51 resulting in a binding, locking action in which relative movement is eliminated and the shaft 46 is clutched to the flywheel 44. This is the action which takes place when the shaft 46 and the driving disc 53 rotate under the force provided by the torque spring I 2.

The operation of the timer constructed in accordance with the present invention is believed to be clear from the foregoing. Let it be assumed that the torque motor I6 is energized by current received through its leads 6 and 1, the control switch 8 being in its dotted line closed position illustrated in Figure l. The motor is so designed and constructed that it can remain energized without injur and the shaft l9 and the connected shaft 22 have been rotated in a counterclockwise direction, as viewed in Figure 2, until the lever 36 is in contact with and is held against the stop pin 38. Let it now be assumed that that event or act occurs which is to initiate the time delay period and as a result thereof switch 8 is opened. Immediately current to motor l0 through the leads 8 and l is cut off and the motor is de-energized. Instantly torque spring I2 is free to rotate large gear 28 in a clockwise direction, as viewed in Figure 2, its force no longer being overcome by the motor torque. The initial movement of the gear 26 under the spring force produces rotation at higher speed in gear-connected shaft 46 and with it the driving disc 53, both rotating counterclockwise, as viewed in Figure 2. Immediately the smaller discs 56 are wedged between the driving disc 53 and their individual pivotal pins 51, and the flywheel 44, with its relatively great mass and inertia, is clutched to shaft 48 and the spring I 2 is loaded by its flywheel effect. Spring |2 performs its function and rotates shaft 22 at the speed permitted by this load and switchactuating lever 36 moves in a clockwise direction from its initial position adjacent pin 38 to its final position adjacent pin 39 shown in Figure 2. During this movement its leadin chamfered edge 42 has made contact with and has displaced switch-actuating plunger element 32 resulting in the operation of switch 3|, and opening or closing of the contacts thereof, whichever may be preferred. The time interval required for the pivotal movement of lever 36 from its initial position adjacent pin 38 into position to actuate the switch element 32 has been determined by the acceleration imparted to shaft 22 by the spring l2 and that, of course, has been determined by the relationship between the torque of the spring and the retarding inertia load provided by the flywheel unit I The values of these factors are so selected that the plunger 32 is displaced and the switch 3| actuated at a predetermined time interval following the de-energization of motor l0 and the accompanying instantaneous application of the torque of spring l2.

Let it now be assumed further that the timer has effected its purpose and is to be reset. The switch 8 controlling the circuit of motor I0 is alimciofidffttiiatris simian iri I ig-energized 'Motorsl'iaft lafcormectedsli and-gthe.levenlflaare instantly snapped to th'eir oidginahpositionai'idwithout any braking effect of thegflywheel. Having-reached its originaliposittioniagainst the stopi'uwlcvemfl remainsithere being held by the motor which remains energized and ready for a subsequent operation upon the recurrence of that act or event which causes the switch 8 to be opened.

While the particular apparatus herein shown and described in detail is fully capable of attaining the objects and providing the advantages hereinbefore stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or designherein shown other than as defined in the appended claims.

1. In a device of the class described, an element to be controlled, a movable element to actuate said; element to be controlled, said movablefele merit being movable between limits, first forceexerting means continuously exerting a force on said movable element to displace it to actuate said element to be controlled, second electrically energized force-exerting means normally energized and exerting a force on said movable element suflicient to prevent its displacementby' said first force-exerting means and also sufficient to return said movable element to its initial position against the opposing force of said first forceexerting means, retarding means comprising a mass to retard by its own inertia the speed of displacement of said movable element, and means to connect said retarding means to said movable element upon its displacement by said first forceexerting means only.

2. In a timer of the type adapted to impress a predetermined time delay between an initial act and a subsequent act, a rotatable shaft the position of which is to be controlled to control the occurrence of said subsequent act, resilient means continuously urging said shaft in one direction of rotation, normally energized electrical forceexerting means to rotate said shaft normally opposing the force exerted by said resilient means and holding said shaft against rotation by said resilient means, retarding means comprising a 'mass to retard by its own inertia the speed of rotation of said shaft, and a clutch to connect said "retarding means to said shaft upon the rotation of said shaft by said resilient means only.

3. In a timer of the type adapted to impress a predetermined time delay between an initial act and a subsequent act, a rotatable shaft the position of which is to be controlled to control tb'ps to lifiii the flotation f said 'sliaf t rcti'om-" an inrtia mass to retard the a-easier; m of said shaft, and a 'clu'tch to con- '10 "riectf'sai'd inertia m'ass to said"shaft upon its ro- "tatiorfbfsaid torque"'sl5rihg"orily.

-4. e n a-timer'bf the type "adapted F to" impress a fdtrmihed 'time" delay 1 between farifinltial and aisubsequent =act',- *a-" rotatable shaft the lo position of"Whi ch is; to be' controlled 5 t ohtfbl "Tth "occurrerfcebf said subsequent- "act; atorque ng urgmg saldshaftfirfone' directiori'iof "rotion; ainormally en'ergized electric T tsrqussmot'orioppos'in'g 'therotational" force exerted "on sai'd "sfifficientlyigreater thanthe torque ofs'aidispring "asf'to-tehaible' it to 1 snap said 'sl iaft to a 'sta'rtihg fp'osition against theppposition of said-sprin'g- 'aiid "tdretam it there with said' spring inaldaded condition, stops determining the starting and final positions of said shaft, a mass having relatively great inertia as compared to all supplemental forces to retard the acceleration of said shaft, and a clutch to connect said mass to said shaft upon its rotation by said torque spring only. 5. In a timer of the type adapted to impress a predetermined time delay between an initial act and a subsequent act, a rotatable shaft the position of which is to be controlled to control the occurrence of said subsequent act, a torque spring urging said shaft in one direction of rotation, a normally energized torque motor opposing the rotational force exerted on said shaft by said spring, said motor exerting a torque sufficiently greater than the torque of said spring as to enable it to snap said shaft to a starting position against the opposition of said spring and to retain it there, a lever fixed to said shaft, stops fixing the range of pivotal movement of said lever upon the rotation of said shaft, a fiywheel, and means connecting said flywheel to said shaft including a unidirectional clutch operative to connect said flywheel to said shaft only upon the rotation of the latter under the actuation of said spring.

6. In a timer of the type adapted to impress a predetermined time delay between an initial act and a subsequent act, a rotatable shaft the position of which is to be controlled to control the occurrence of said subsequent act, a torque spring urging said shaft in one direction of rotation, a normally energized torque motor opposing the rotational force exerted on said shaft by said spring, said motor exerting a torque sufliciently greater than the torque of said spring as to enable it to snap said shaft to a starting position against the opposition of said spring and to retain it there, a lever fixed to said shaft, stops fixing the range of pivotal movement of said lever upon the rotation of said shaft, a circuitcontrolling electric switch having an actuating element positioned as to be contacted and actuated by said lever in its pivotal movement from said starting position to said final position, a flywheel to provide an inertia load to said shaft upon the rotational acceleration thereof, and means connecting said flywheel to said shaft including gears to increase the speed of said flywheel relative to the speed of said shaft, and a unidirectional clutch operative to connect said flywheel to said shaft only upon the rotation of the latter under the actuation of said spring.

7. In a device of the class described, a frame having a base and a wall, a torque motor mounted on said base with its shaft extended toward said wall, a second shaft connected to said motor shaft and extended through said wall, said second shaft fixedly carrying a large gear upon one side of said wall and a lever upon the opposite side, a torque spring encircling said second shaft connected between said wall and said gear to exert a force tending to rotate said second shaft against the force" exerted by said motor and adapted to do so upon'the de-energization of said motor, stops carried by said wall to limit the travel of said lever and the angular rotation of said second shaft, a circuit-controlling electric switch including an actuating element carried by said wall and extended into the path of said lever to receive an actuating force therefrom, a third rotatable shaft carried by said wall and extended parallel to said first and second shafts, a pinion fixed on said third shaft meshing with said gear on said second shaft, a flywheel freely rotatable 8 on said third shaft, and a unidirectional clutch to connect said flywheel to said third shaft upon its rotation under the actuation of said spring only.

ALONZO W. NOON.

REFERENQES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,053,143 Frederick Sept. 1, 1936 2,055,707 Rippl Sept. 29, 1936 2,143,692 Haar Jan. 10, 1 939 2,163,419 Warren June 20,1939 2,223,207 Ellis Nov. 26, 1940 2,464,316 Jeanneret Mar. 15,1949 2,479,922 Gates et a1 Aug. 23, 1949 FOREIGN PATENTS Number Country Date 558,488 Great Britain Jan. 7, 1944 

